Wilkie's family say he passed away "peacefully" following a "brave battle with cancer."

Born in Sri Lanka to Scottish parents, Wilkie won his first major medal with a bronze at the 1970 Commonwealth Games in Edinburgh, Scotland. 

Racing at his first Olympics in Munich in 1972, Wilkie earned silver in the 200m breaststroke, then collected World Championship gold at the first edition of the World Aquatics Championships the following year in Belgrade. Wilkie's win at the Worlds started a staggering four-year unbeaten streak in the 200m breaststroke.

Image Source: David Wilkie with University of Miami swimming coach Bill Diaz during a training session in 1976. Wilkie was a 13-time NCAA All American while swimming for the Hurricanes from 1973-1976 (Tony Duffy/Getty Images)

In 1975, Wilkie completed a 100m and 200m breaststroke golden double at the World Aquatics Championships in Cali, Colombia en route to being voted British Sports Personality of the Year.

Wilkie's crowning moment in the pool came in Montreal, with his Olympic triumph in the 200m breaststroke. His 2:15.11 sliced more than three seconds off the then-World Record. He also earned silver in the 100m breaststroke in Canada. Wilkie's 200m breastroke win in Montreal was all the more outstanding as Team USA won gold all the other 13 men's swimming events at the Games. 

Image Source: David Wilkie with his 200m breaststroke gold from the 1973 World Aquatics Championships (Gerrard/Daily Express/Hulton Archive/Getty Images)

Wilkie also recorded a World Record in the 200m Individual Medley at the 1974 European Championships in Vienna, Austria, a meet where he also won the 200m breaststroke and silver in the 4x100m Medley Relay. 

In 1977, Wilkie was awarded as a Member of the Most Excellent Order of the British Empire (MBE), a distinction given for "achievement or service in and to the community which is outstanding in its field and has delivered sustained and real impact which stands out as an example to others."

Fellow Team GB Montreal 1976 teammate Sharron Davies described Wilkie as "an inspiration" in a tribute post. 

Wrote Davies: "I am so sad to hear of the loss of Olympic champion superstar breaststroker, my first crush & definitely an inspiration, proud Scotsman David Wilkie who died earlier today, sleep tight old friend."